Temperature responsive switch



Nov. 2, 1954 R. L. PERL TEMPERATURE RESPONSIVE swr'ncR 2 sheets-sheet 1 Filed Nov. 20, 1950 Q my m, V x -Il W wr W .Q vl xmwm www, p. B \O N m, %v%\ Q 4 Q E mw\ 1.9m 12j wm Nv E I s RJ A RRR RR WR Il l Nov. 2, 1954 R. L. PERL TEMPERATURE RESPONSIVE SWITCH 2 Sheets-Sheet 2 Filed Nov. 20, 1950 my WP WL d l m 7 E we g a 7 UHU .1 d w mw. @o f f7 Hzzv.

United States atent O TEVIPERATURE RESPONSIVE SWITCH Richard L. Perl, Galion, Ohio, assignor to The Tappan Stove Company, Mansfield, Ohio, a corporation of Ohio Application November 20, 1950, Serial No. 196,684

Claims. (Cl. 200-137) This invention relates to automatic ignition mechanism for the top burners of cooking ranges using gaseous fuel.

It is especially adapted for use with a plurality of spaced burners and includes a gaseous fuel pilot burner which is centrally disposed with respect to the main burners. The pilot burner is ignited by an electric resistance ignition element and the main burners are ignited by the pilot burner through ilash tubes which extend from the main burners into close proximity with the pilot burner. The supply of gas to the pilot burner is controlled by the valves for the main burner. The opening of any of the main burner valves to supply gas to a main burner will also admit gas to the pilot burner. The electric ignition element is in an electric circuit which includes a normally closed switch and a plurality of normally open switches. There is a normally open switch operatively associated with each burner valve in such a manner that the opening of the valve will close the switch, and conversely the closing of the valve will open the switch. The normally closed switch is arranged to be opened by a thermostatic element which is mounted in position to be heated by the pilot burner after it has been ignited by the electric ignition element. The opening of the normally closed switch will break the circuit to and de-energize the electric ignition element which need not be energized after the pilot burner has been ignited. In operation it is only necessary to open the selected burner valve. The opening of the valve admits gas to the main burner and to the pilot burner and closes the normally open switch associated therewith. The closing of the normally open switch will make the circuit to and energize the electric resistance element which will then ignite the pilot burner. The pilot burner will ignite the main burner through its flash tube, and will heat the thermostatic element, and the thermostatic element when heated will open the normally closed switch and break the circuit to and de-energize the electric resistance element. In the event the pilot burner should be extinguished for any reason while the gas is still turned on the thermostatic element will cool and close the normally closed switch which will re-energize the electric resistance element and re-ignite the pilot burner.

This application is a modiiication of the devices shown in my co-pending applications, Serial No. 196,681, tiled November 20, 1950, and Serial No. 196,683, led November 20, 1950.

The principal object of the invention is to provide a very simple and efficient automatic ignition mechanism for the top burners of cooking ranges.

Another object of the invention is to provide in a mechanism of this character, which includes a pilot burner and an electric resistance element which ignites the pilot burner, means operative to automatically de-energize the electric resistance element after the pilot burner has been ignited.

Other and more limited objects of the invention will be apparent from the following specification and the accompanying drawings forming a part thereof wherein:

Fig. 1 is a diagrammatic layout showing the invention applied to a pair of spaced gaseous fuel burners;

Fig. 2 is an enlarged top plan view of the removable control unit;

Fig. 3 is an enlarged bottom plan View of the removable control unit;

Fig. 4 is a central longitudinal vertical section, taken S0 substantially on the line 4-4 of Fig. 2; and

2,693,517 ipatentecl Nov. 2, 1954 Fig. 5 is a transverse section, taken on the line 5 5 of Figs. 1 and 4.

The scale of Fig. l is approximately half size and the scale of Figs. 2 to 5 is approximately three times the scale of Fig. 1.

Referring now to the drawings by reference characters, the numerals 1 and 2 are applied to a pair of spaced top burners of a cooking range. Gaseous fuel is supplied to the burner 1, from a supply manifold 3, through its mixing tube 4; and to the burner 2, from the manifold 3, through its mixing tube 5. A pair of cut-oftE valves 6 and 7 control the supply of gas to the burners 1 and 2, respectively. A pilot burner 8 is suitably mounted between the free ends of a pair of aligned flash tubes 9 and 1i) which are carried by the burners 1 and 2, respectively. Gaseous fuel is supplied to the pilot burner 8 from the manifold 3 through the valve 7 and the conduit 11 or through the valve 6 and the conduits 12 and 11. The cut-off valves 6 and 7 are so constructed that when either one is turned on to supply gas to one of the main burners 1 and 2 gas is also supplied to the pilot burner 8. The pilot burner 8 is ignited by an electric resistance ignition element 13 when it is energized, and the main burners 1 and 2 are ignited by the pilot burner 8 through the flash tubes 9 and 10. The electric ignition element 13 is mounted in operative relation to the pilot burner 8 on an insulating block 14 of a removable control unit generally indicated by the numeral 15. The energization of the electric ignition element 13 is controlled by a pair of normally open switches 16 and 17 and a normally closed switch 18. The normally open switch 16 is operatively associated with the valve 6 and comprises the contacts 19 and 20 and the bridging conductor bar 21. The switch 16 is adapted to be closed through the medium of a cam section 22 carried by the valve stem 23 of the valve 6 and a link 24 simultaneously with the opening of the valve 6 and to be opened simultaneously with the closing of the valve 6. The normally open switch 17 is operatively associated with the valve 7 and comprises the contacts 25 and 26 and the bridging conductor bar 27. 1t is adapted to be closed through the medium of a cam section 28 carried by the valve stem 29 of the valve 7 and a link 30 simultaneously with the opening of the valve 7 and to be opened simultaneously with the closing of the valve 7. The switch 18 is incorporated in the control unit 15 and is adapted to be opened by a thermostatic element 31 which is also incorporated in the control unit 15 in position to be heated by the llame from the pilot burner 8. The specific construction of the control unit 15 and the component parts thereof will be described in detail hereinafter.

In operation it is only necessary to turn on the control valve of the selected main burner. The turning on or opening of the valve will close the associated normally open switch 16 or 17 and supply gas to both the main burner and the pilot burner. The closing of the switch 16 or 17 will make the circuit to and energize the electric ignition element 13 which Will then ignite the pilot burner. The main burner will then be ignited through its flash tube by the pilot burner. After ignition the pilot burner will also heat the thermostatic element 31 which after being heated will open the normally closed switch 18 and maintain it open as long as the thermostatic element 31 is heated by the pilot burner. The opening of the normally closed switch 18 breaks the circuit to and de-energizes the electric ignition element 13 which need not remain energized after the pilot burner has been ignited. If after one main burner has been ignited the other main burner is turned on it will be ignited through its flash tube by the pilot burner which has already been ignited, it being understood that the pilot burner is arranged to burn as long as either of the main burners is turned on. If the pilot burner should be extinguished for any reason while either of the main burners is turned on, the thermostatic element 31 will immediately cool and allow the switch 18 to close which will re-establish the circuit to and re-energize the electric ignition element 13 which will then re-ignite the pilot burner 8.

The electric circuit which includes the electric ignition element 13, the normally open switches 16 and 17 and the normally closed switch 18 will nowbe traced, assuming tirst that the burner 1 is turned on by opening the valve 6. The opening of the valve 6 will supply gas to the main burner 1 and the pilot burner 8 and will close the normally open switch 16. As soon as the switch 16 is closed current will flow from one side 32 of the line through the leads 33 and 34 to the contact 19 of the switch 16 through the bar 21 to the contact 20. From thecontact the current will flow through the lead 35 to the terminal 36 of the electric resistance ignition element.13 and then through the ignition element 13 to the terminal 37 thereof. From the terminal 37 the current will flow through the switch 18 and back to the other side 39 of the line through the lead 40, completing the circuit to and energizing. the ignition element 13, which will remain-energized until the thermostatic element opens the switch 18 and breaks the circuit. Assume that the main burner 2 is irst` turned on by opening the valve 7. The opening of the valve 7 will supply gas to the main burner 2 and the pilot burner 8 and close the normally open switch 17. As soon as the switch 17 is closed current will ow from the side 32 of the line through the lead 33, switch 17 and lead 41 to the lead 35. From the lead v the current will flow through the ignition element 13, switch 18 and back to the other side 39 of the line as previously described. The turning on of either one of the main burners after the other main burner has been turned on and ignited along with the pilot burner will not energize the electric ignition element 13 as the circuit thereto cannot be completed since the thermostatic element 31 is holding the switch 18 open.

The control unit 15 comprises aframe 50, the electrical resistance ignition element 13 and its carrier block 14, the switch 18 and the thermostatic element 31. The frame is formed of. thin sheet metal and comprises a top wall 51 and a pair of spaced side walls 52 and 5 3 which are integral with the top wall 51 and extend downwardly therefrom. The inner ends of the Side walls 52 and 53 are connected by a vertical end wall 54 and the top wall 51 has anenlarged opening 55 therethrough adjacent the end wall.54. The lower edgesof the side walls 52 and 53 are notched at each side of the opening 5S as indicated at 56. They unit 15`is removably supported between the burners 1 and 2 by an arm 57 on which the outer end of the frame 50 rests and the flash tubes 9 and 10 which engage the side walls 52 and 53 inthe-notches 56. When in position the opening 55 of the top wall 51 is disposed over the pilot burner 8 so that when itis ignited it will project. a flame up between.

the side walls 52' and 53. The. electrical resistance ignition element 13 is removably secured between the terminals136 `and 37 carried by the block 14 of insulating materia 52 and 53 in the opening 55 inposition to maintain the ignition element 13 in operative relation to the pilot burner 8.

The. top wall 51 is slotted longitudinally along each side wall 52 and 53 as indicated at 58 and 59. The outer ends of the slots 58 and 59 are connected by a transverse slot 60 to provide an elongated exible tongue 61.

transverse slot 62 intermediate the inner ends of the.

slots 58 and 59 is provided to give greater ilexibility to the tongue 61.

The normally closed switchV 18 comprises a normally stationary contact 65 and a movable Contact 66. The stationary contact 65 is adjustably mounted on a metal arm 67 which is secured by screws 68 to a block of insulation 69 secured to the top wall.51 by a screw 70. The movable contact 66 is carried by the free end of the. tongue 61. The terminal 37 is connected to the arm 67 by a bar 71.

The thermostatic element 31 is formed from a single piece of sheet metal and comprises an elongated arm '72 and a shorter arm 73 which is disposed in the plane ofthe arm 72 and extends substantially at right. angles to the arm 72. The arm 72 extends across the opening 55', in position to be heated by the pilot burner. 8, and is rigidly secured to the end wall 54. at 74; and the arm 73 extends upwardly from the arm 72 and is rigidly securedto theundersideof the tongue 61 adjacent the slot 62: at 75'.. After' the pilot burner 8: has been ignited` The block 14 is mounted between the side walls.

element 31. The heating of the arm 72 will elongate it which will llex the tongue 61 upwardly and raise the contact 66 out of engagement with the contact 65, thus opening the switch 18 and breaking the circuit to the electrical resistance ignition element 13.

From the foregoing it will be apparent to those skilled in this art that I have provided a very simple and e1 cient mechanism for accomplishing the objects of the invention.

It is to be understood that I am not limited to the specific construction shown and described herein asV vari# ous modifications can be made therein within the spirit of the invention.

What is claimed is:

l. A thermally responsive switch mechanism compris ing a frame having. a top wall, a flexible tongue formed in said top wall as an integral part thereof, a normally closed switch mounted on said frame, and a thermostatic element independent of said. tongue: carriedl by said -frame, said thermostatic element being operative when heated to flex said tongue, and said tonguebeing operative when exed to open said normally closed switch.

2. A thermally responsive switch. mechanism comprising a frame having a top wall, a flexible-tongue formed in said top wall aszan integral part thereof, a normally closed switch mounted on said. frame, said switch* comprising a stationary contact carried by saidA frame and a movable contact carried'by the free end of'said tongue, a thermostatic element independent of said tongue car-l ried by said frame, and operative connections between` said thermostatic element andisaid tongue through which' said tongue is flexed to move said movable contact outl of engagement with said stationary contact when said thermostatic element is heated.

3. A thermally responsive switch mechanism compris-` ing a frame having a top walland an end wall, a tiexible.l tongue formed in said top wall as an integral partthereof, a normally closed switch mounted on said frame',- said switch comprising a stationary contact carried by said frame and aV movable contact carried by the free endv of said tongue, and a thermostatic element independentof said tongue having one end'thereof rigidly connected to said end walland the other end thereof rigidly-cony` nected to said tongue, said thermostatic element being operative when heated to tiex saidA tongue. to move saidf movable contact out of engagement with said'stationaryr contact.

4. A thermally responsive switch mechanism comprising a frame having a top wall andV an endwall, a exible tongue formed in said'top wall asan integral part there-f of, a normally closed switch mounted on said frame, said switch comprisinga stationary contact carried by.' said frame and a movable contact carried by thek free endof said tongue, and a thermostatic element formed' from a single piece. of flat sheet metal and having one'A end'thereofl rigidly connected to saidl end wall and"- the other end thereof.rigidly connected to said'tongue, said thermostatic element being operative whenheated tol flex said tongue to move said movable contactout off engagement with said stationary contact.

5. A thermally responsive switchl mechanism. comprising a frame having a top wall and anend wall, afexibleL tongue formed in saidtopwall as anintegral parttthere of, a normally closed switch mountedV on said frame, said switch comprising a stationarycontact carried'by said frame and a movableV contact carried by theY free end of said tongue, and a thermostatic element comprising two integral angularlyv disposed thin sheetrnetal armsl in the. same plane, oneof saidv arms being rigidly'y connectedto said end wall andthe other ofsaid` arms being rigidly connected to said tongue, .said thermostatic.

element being operative when heated to flex said tongue; to move said movable contact out of engagement' with" said stationary contact.

References Cited. inthe le ofi this'patent..

UNITED STATES PATENTSY Number 5 UNITED STATES PATENTS Number Name Date Dixon. Feb. 12, Spiro Dec. 5, 5 Beam Mar. 5, 1940 Betz Nov. 12, 1940 6 Name Date Ragan Sept. 22, 1942 Rodgers Jan. 1, 1946 Altman July 25, 1950 Smith Feb. 3, 1953 

